The following commands are available in the Edit menu of all diagram 
editors. The edit menu can be found in the menu-bar of the main window 
or can be popped up by pressing the 3rd mouse button in the drawing 
area.


Undo (Ctrl+U) 
------------------
Undo the last issued command. The name of the command that can be 
undone is written in the undo menu item. When a command is undone
it can be redone. The redo menu item will list that command. Undo
is multi-level.

Redo (Ctrl+R)
-------------
Redo the last issued command. The name of the command that can be 
redone is written in the redo menu item. When a command is (re)done
it can be undone. The undo menu item will list that command. Redo
is multi-level.

Cut (Ctrl+X)
------------
Put the selected shapes into the buffer. The shapes are removed from 
the diagram.

Copy (Ctrl+C)
-------------
Copy the selected shapes into the buffer. The shapes are not removed 
from the diagram.

Paste (Ctrl+Y)
-------------
Copy the buffer contents into the diagram. A 'paste box' will be 
attached to the mouse which can be positioned at any position in the 
drawing area.

Duplicate 
---------
It is possible to represent one node by several instances of the same 
shape. The duplicate command creates duplicate shapes of the selected 
nodes. The new duplicate shapes are positioned by means of a paste box.
When a node has two or more duplicate shapes then all these shapes 
have a small asterisk in their top-left corner.

When the label of a duplicate shape is updated then all the other 
duplicate shapes are updated too and when a node is deleted (with 
Delete) then all the duplicate shapes of this node are deleted too by 
that command.

Delete (Ctrl+D) 
-----------------
Delete the selected shapes from the diagram. When all the shapes of 
a duplicate node are deleted then the node itself is deleted too. 
But you can delete individual duplicate shapes as well (this will be 
asked in a pop-up dialog).

Delete All 
----------
Delete all nodes and edges from the diagram after that you were asked 
if you are really sure about that.

Same Size 
---------
Make the selected nodes the same size as the first selected node.

Select All 
----------
Select all shapes in the diagram.

Align Nodes 
-----------
Align selected nodes to the first selected node according to the align 
type that is selected from a dialog window.

Convert From/To Curves 
-----------------------
All selected curved lines are changed into segmented lines. All lines with
three segments become curves.